From: Jan Beulich <jbeulich@suse.com>
Date: Fri, 31 Oct 2014 10:31:11 +0000 (+0100)
Subject: VMX: values written to MSR_IA32_SYSENTER_E[IS]P should be canonical
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~4118
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/%22bookmarks://%22/%22http:/www.example.com/cgi/%22https:/%22bookmarks:/%22?a=commitdiff_plain;h=93cc5c6f1641e90eb120826d42f103b7726efb8e;p=xen.git

VMX: values written to MSR_IA32_SYSENTER_E[IS]P should be canonical

A recent KVM change by Nadav Amit <namit@cs.technion.ac.il> helped spot
that we have the same issue as they did.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Tim Deegan <tim@xen.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
---

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 29aaad4a4a..79a69b1d0c 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -2273,9 +2273,13 @@ static int vmx_msr_write_intercept(unsigned int msr, uint64_t msr_content)
         __vmwrite(GUEST_SYSENTER_CS, msr_content);
         break;
     case MSR_IA32_SYSENTER_ESP:
+        if ( !is_canonical_address(msr_content) )
+            goto gp_fault;
         __vmwrite(GUEST_SYSENTER_ESP, msr_content);
         break;
     case MSR_IA32_SYSENTER_EIP:
+        if ( !is_canonical_address(msr_content) )
+            goto gp_fault;
         __vmwrite(GUEST_SYSENTER_EIP, msr_content);
         break;
     case MSR_IA32_DEBUGCTLMSR: {